Panning/zooming now updates #map=<zoom>/<lat>/<lon> in the URL, and loading a URL with one already opens at that view instead of the default center — so copying the URL bar shares the exact spot someone's looking at, and a page reload doesn't lose the current view either. This is MapLibre GL JS's own built-in Hash control (hash: "map" on the Map constructor) — it already does exactly this, replaceState and all, no custom code needed.